IEEE C802.16j-07/547
Project
IEEE 802.16 Broadband Wireless Access Working Group <http://ieee802.org/16>
Title
Clarifications on RS Network Entry Procedures
Date
Submitted
2007-11-12
Source(s)
Relay TG network entry and ranging ad hoc Group
loa@iii.org.tw
Chairs: Kanchei (Ken) Loa and Peiying Zhu
pyzhu@nortel.com
Re:
IEEE 802.16j-07/043: “IEEE 802.16 Working Group Working Group Letter Ballot #28”
Abstract
This contribution proposes modification on RS Network Entry
Purpose
Text proposal for 802.16j Draft Document.
Notice
Release
Patent
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Clarifications on RS Network Entry Procedures
Chairs: Kanchei (Ken) Loa and Peiying Zhu
Relay TG network entry and ranging ad hoc Group
Introduction
This contribution is proposed to clarify the RS network entry procedures. It covers the following comments:
Comment#
558
560
561
617
645
647
651
653
655
subclauses
6.3.9
6.3.9.1
6.3.9.1
6.3.9.16.3
6.3.9.16.3.2
6.3.9.16.3.2
6.3.9.16.3.3
6.3.9.16.3.4
6.3.9.16.4
Authors
Ronald
Peiying
Gamini
Gamini
Mike
Shulan
Gamini
Mike
Mary
0
Mao
Zhu
Senarath
Senarath
Hart
Feng
Senarath
Hart
Chion
Type
Technical
Technical
Editorial
Technical
Technical
Technical
Editorial
Technical
Technical
IEEE C802.16j-07/547
657
658
660
664
665
1047
6.3.9.16.3.4
6.3.9.16.3.4
Hyunjeong
Gamini
Yousuf
Erik
Mike
Mary
6.3.9.16.4
6.3.9.16.4
6.3.9.16.4
Kang
Senarath
Saifullah
Colban
Hart
Chion
Technical
Editorial
Editorial
Technical
Technical
Technical
Technical issues that we proposed to resolve in this contribution are following.
1.
The procedure of figure 72a does not include RS in MS mode of operation which is defined in section
6.3.9.16.3.1.2, and the current RS initialization procedure is somewhat complex and confusing. In essence,
the RS network entry procedure is independent from the procedure of RS path selection and configuration.
(Defer pending resolution of RS grouping comments (#640))
2.
Some clarifications for the paragraph. In addition, a MS also reports these information, do we really need to
have this paragraph?
3.
RS Synchronization procedure after entering to the RS mode of operation is not included in the proper
section. Currently it is described in Section 6.3.9.16.3.4. The two paragraphs should be moved to Section
6.3.9.1 which describes synchronization for the RS.
4.
Current RS network procedure is not clearly summarized at the beginning of the RS initialization Section
(Section 6.3.9.16.3). The following few lines may add clarity.
5.
This has text (in 6.3.9.16.3.2) that should be divided into 6.3.9.16.3.3 and 6.3.9.16.3.4.
6.
In section 11.23.1, “Preamble indexes reserved for moving relay station” has been defined. However, this
TLV seems can only be used in session 6.3.9.16.3.2, which is the initial network entry of mobile RS. There
is no need to reserve dedicated preambles for mobile RS in the network entry procedure for the preamble is
configured by MR-BS. The mobile RS shall perform the same network entry procedure with that of the
fixed RS.
(Defer pending resolution of RS_CD message changes #385)
7.
At this stage, the MR-BS may request RSs to perform a complete neighborhood discovery using both the
preambles and the R-ambles. Although it is understood that MR-BS send RS-CD message to the RS
performing the network entry, it needs to be mentioned exclusively for clarity.
8.
Needs some modification to explain what should occur during the configuration phase of network entry.
Also there is a lot of unnecessary text that can be removed, as the overview section already indicated when
this phase happens, so all that is required is a brief description of how configuration occurs. Note also that
there is no way of currently specifying which frame the RS should start frame start preamble transmission,
therefore remove this statement. It could be inferred from the RS_CD and RS_Config-REQ that the RS can
choose when to start operating as a RS station.
9.
There are a few questions need to be clarified for this section and also related embedded path management
a) Since this is an optional feature, how is the option indicated? How would a RS know, at network entry, if
it will receive a CID_Alloc_Req and how does MR-BS know if the RS supports this feature?
b) Section 6.3.9.16.4, it seems to be describing both network entry procedures for RS and for MS suggest
to clarify and maybe separate into 2 sections.
c) It is not clear that when CID_Alloc-Req message will be sent to RS during network entry. Is the CID preallcoation happening during network entry?
d) Is the CID range for management connection only? or should be 2 management connection and the rest
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IEEE C802.16j-07/547
for transport CID?
(Defer pending resolution of CID allocation issues (Saito, Jung Je, Aik))
10. RS configuration response message is not defined. To configure the operational parameters, RS
configuration recommendation message and RS configuration request message are used.
11. There is no RS Configuration response message. This message name has been since changed as "RS
Configuration recommendation message".
12. Remove lines 15 through 17 inclusion of "frame start preamble index" is already mentioned on line 6.
13. What is "localized"? The term occurs only in this section and is not defined. "Embedded path management"
is another term that is not defined either.
(Defer pending resolution of CID allocation issues (Saito, Jung Je, Aik))
14. Change this section to match with the mode "RS operating in local CID allocation mode". Also there are
some technical errors in the message usage and reference to BS (not MR-BS)
(Defer pendin resolution of #565 (potentially only need to consider 6.3.9.16.4.1))
15. The title of 6.3.9.16.4 is Optional network entry procedures with localized RS. What does "localized RS"
mean? either define it somewhere or remove localized RS from the titles
(defer pending resolution of comments being dealt with by Aik (by 664);
Issue 3 is covered by #565; Issue 1 & 2 still open)
In order to facilitate the incorporation of this proposal into IEEE 802.16j standard, specific changes to the draft
standard P802.16j/D1 are listed below.
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IEEE C802.16j-07/547
Specification Changes
[Modified following subclause as indicates:]
6.3.9.16.3.1 6.3.9.31 RS grouping
[Move the following subclause to 6.3.10.3.1.2 (see C802.16j-07/525r2 or latter version):]
6.3.9.16.3.1.1 MS network entry procedures
[Move the paragraphs to the new subclause “6.3.9.16 RS Network entry and initialization”, and delete the
following subclauses:]
6.3.9.16.3 RS network entry and initialization
6.3.9.16.3.1.2 RS network entry procedures
6.3.9.16.3.2 Moving RS preamble selection
6.3.9.16.3.3 Neighbor station measurement report
6.3.9.16.3.4 Relay station operational parameter configuration
6.3.9.16.3.5 Initial path selection procedure
6.3.9.16.4 Optional network entry procedure with localized RS
6.3.9.16.4.1 CID pre-allocation to localized RS
[Delete following subclause since it is empty (see accepted contribution C802.16j-07/459r6):]
6.3.9.16 Support for network entry and initialization in relay mode
6.3.9 Network entry and initialization
Systems shall support the applicable procedures for entering and registering a new SS or a new RS or a new
node to the network. All network entry procedures described hereunder through and including 6.3.9.13 apply
only to PMP operation and PMP operation with MR support. The network entry procedure for Mesh operation
is described in 6.3.9.14.
The procedure for initialization of an SS and an RS shall be as shown in Figure 75 and Figure 75a, respectively.
This These figures shows the overall flow between the stages of initialization in an SS and an RS. This These
shows no error paths and is shown simply to provide an overview of the process. The more detailed finite state
machine representations of the individual sections (including error paths) are shown in the subsequent figures.
Timeout values are defined in 10.1.
Figure 75—SS initialization overview
The procedure for initialization of an RS shall be as shown in Figure 72a. For the RS the stages g), h), i) and j)
in the figure 55 are not required, for all other stages the RS shall behave in the same manner as an SS during
network entry unless otherwise specified in the subclauses of 6.3.9. The more detailed finite state machine
representations of the individual sections (including error paths) and the timeout values shall be the same as
those provided for the SS, unless otherwise specified.
[Replace “Path selection” by “Access station selection”]
[Replace “Path selection complete” by “Access station selection complete”]
Figure 72a 75a—RS initialization overview
The procedure can be divided into the following phases:
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IEEE C802.16j-07/547
a) Scan for DL channel and establish synchronization with the BS
a1) Perform access station selection (RS only)
b) Obtain Tx parameters (from UCD message)
c) Perform ranging
d) Negotiate basic capabilities
e) Authorize SS/RS and perform key exchange
f) Perform registration
g) Establish IP connectivity (SS only)
h) Establish time of day (SS only)
i) Transfer operational parameters (SS only)
j) Set up connections (SS only)
k) Obtaining neighbor station measurement report (RS only)
l) Perform access station selection (RS only)
m) Configure operation parameters (RS only)
Implementation of phase e) is optional. This phase shall be performed if both SS/RS and BS support
Authorization Policy. Implementation of phases g), h), and i) at the SS is optional. These phases shall only be
performed if the SS has indicated in the REG-REQ message that it is a managed SS.
Implementation of phase a1), k), l) are optional. The MR-BS may instruct the RS to omit phases a1), k), l), m)
by the RS network entry optimization TLV in the RNG-RSP message.
6.3.9.1 Scanning and synchronization to the downlink
Insert the following text at the end of 6.3.9.1:
RS follows the scanning and synchronization procedure similar to that of the SS. In addition, however, the RS
may store preamble index and signal strength in order to report the stored values to the serving MR-BS after
registration.
6.3.9.2 Obtain DL parameters
6.3.9.2.1 Access station selection
The access station selection procedure may be performed in either phase a1) or phase l). If the path selection is
processed in phase a1) (prior to “obtain uplink parameters”), the MR-BS and the RS may transmit the TLV
encoded parameter end-to-end Metric in the DCD message to support access station selection in the MR
network. The use of these TLV encodings is defined in section 11.4 in Table 606. The RS attempting network
entry may obtain the DCD TLV encodings sent by neighboring RSs and MR-BSs to select a desired access
station to enter the MR network through it. The RS shall then proceed with the rest of the network entry
procedure as defined in Figure 75a with the desired access station.
6.3.9.3 Obtain UL parameters
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6.3.9.4 Message flows during scanning and UL parameter acquisition
6.3.9.5 Initial ranging and automatic adjustments
6.3.9.5.1 Contention-based initial ranging and automatic adjustments
6.3.9.7 Negotiate basic capabilities
6.3.9.8 SS authorization and key exchange
6.3.9.9 Registration
6.3.9.9.2 MR-BS and RS behavior during registration
[Insert the following text at the end of 6.3.9.9.2]:
When an RS performs registration, MR-BSs and RSs shall follow the same steps in previous subclause 6.3.9.9
with the following modification.
Wait for REG-RSP
REG-RSP
Stop T6
Yes
Perform neighbor
meas. report?
No
Start TConfigCmd
Perform neighbor measurement report
Wait for RS_Config-CMD
Figure 94a— Handling REG-RSP first reception at a RS
Wait for RS_Path-REQ
REG-RSP
Stop TPathReq
Yes
Perform neighbor
meas. report?
No
Start TConfigCmd
Perform neighbor measurement report
Wait for RS_Config-CMD
Figure 94b—Handling REG-RSP retransmission at a RS
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Wait for REG-REQ
REG-REQ
Stop T17
Authorization
Policy support?
No
Yes
Calculate HMAC/CMAC over REG-REQ
Yes
No
HMAC/CMAC Valid?
Yes
Set RS capabilities supported in REG-RSP
REG-RSP with Response = 1
(Message Auth. Failure)
REG-RSP with Response =0 (OK)
Wait for REG-REQ
Perform neighbor
meas. report?
Yes
No
Start TNbrMeas
Wait for RS_NBR-MEAS-REP
Perform operation parameter configuration
Figure 94c— Handling REG-REQ first reception from RS at a MR-BS
Wait for RS_NBR-MEAS-REP
REG-REQ
Stop TNbrMeas
No
Authorization
Policy support?
Yes
Calculate HMAC/CMAC over REG-REQ
Yes
No
HMAC/CMAC Valid?
Yes
Set RS capabilities supported in REG-RSP
REG-RSP with Response = 1
(Message Auth. Failure)
REG-RSP with Response =0 (OK)
Wait for REG-REQ
Yes
Perform neighbor
meas. report?
No
Start TNbrMeas
Wait for RS_NBR-MEAS-REP
Perform operation parameter configuration
Figure 94d— Handling REG-REQ retransmission from RS at a MR-BS
6.3.9.15 Forcing MSs to perform network entry at once
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[Insert the following subclause 6.3.9.16]:
6.3.9.16 RS Network entry and initialization
6.3.9.16.1 RS neighbor station measurement report
During network entry or re-entry, an RS may be required, as indicated in the RS network entry optimization
TLV in the RNG-RSP message, to report (1) the signal strength and preamble index of neighbor non-transparent
stations with unique BSIDs, and (2) signal strength and R-amble index of neighbor transparent stations or nontransparent stations with shared BSIDs. If the RS is a mobile RS, and the RCD message provides the TLV
"preambles indexes reserved for mobile RS, the mobile RS shall report the signal strength and preamble index
for these preambles. MR-BS shall assign the preamble index based on the report from the RS. If measurement
report is required, the RS shall send the RS_NBR-MEAS-REP message (6.3.2.3.68) to the MR-BS after
completion of registration.
Perform neighbor measurement report
RS_NBR-MEAS-REP
Start TPathReq
Change state to “Wait for RS_Path-REQ”
Figure xxx—Handling RCD first reception at a RS
Wait for RS_NBR-MEAS-REP
RS_NBR-MEAS-REP
Perform access station selection
Figure zzz— Handling RS_NBR-MEAS-REP first reception at a MR-BS
6.3.9.16.2 Access station selection
The access station selection procedure may be performed in either phase a1) or phase l). The access station
selection procedure performed in phase l) (prior to “RS operation parameter configuration”) is an optional
procedure as indicated by the RS network entry optimization TLV in the RNG-RSP message. This operation
happens after neighbor station measurement report and before RS operation parameter configuration. During
this operation, the MR-BS shall determine the path (i.e. access station) of this RS based on the reported
neighbour station measurements and other information such as path loading. The MR-BS shall send the
RS_Path-REQ message to the RS to indicate the preamble index of the selected access station. The RS shall
respond with the MR_Generic-ACK message. If the access station indicated in the RS_Path-REQ message is
not the access station the RS currently attaches to, the RS shall perform network re-entry as described in 6.3.9.
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Wait for RS_Path-REQ
RS_Path-REQ
Stop TPathReq
MR_Generic-ACK (RS_Path-REQ)
Yes
No
Change access station?
Start TConfigCmd
Change state to
“Wait for RS_Config-CMD”
Network re-entry via the
selected access station
Figure xxx— Handling RS_PATH-REQ first reception at a RS
Wait for RS_Config-CMD
RS_Path-REQ
Stop TConfigCmd
MR_Generic-ACK (RS_Path-REQ)
Yes
Change access station?
No
Start TConfigCmd
Change state to
“Wait for RS_Config-CMD”
Network re-entry via the
selected access station
Figure yyy— Handling RS_PATH-REQ retransmission at a RS
Perform access station selection
RS_Path-REQ
Start TPathAck
Wait for MR_Generic-ACK (RS_Path-REQ)
MR_Generic-ACK (RS_Path-REQ)
Stop TPathAck
Yes
Change access station?
End
No
Perform operation parameter configuration
Figure zzz— Perform path selection at a MR-BS
6.3.9.16.3 RS operation parameters configuration
During this phase, MR-BS shall determine the RS operation parameters and send an RS_Config-CMD message
to configure these parameters. The message shall contain RS mode, and may contain preamble index, R-amble
index, the allocated management CID for RS operating in local CID allocation mode. When RS shall use a
different frame number offset from the number which the MR-BS transmits, MR-BS shall include RS frame
offset TLV in RS_Config-CMD message. After receiving RS_Config-CMD message, a non-transparent RS
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should keep its synchronization by listening to the R-amble transmitted by its superordinate station because a
non-transparent RS transmits its own frame start preamble. Once an RS is synchronized with the frame start
preamble received from its superordinate station, by knowing the R-amble offset contained in the R-link channel
message (RCD) described in Section 6.3.2.3.62, it can quickly resynchronize with the superordinate R-amble.
Once the synchronization is established using the R-amble, the RS shall respond with the MR_Generic-ACK
message to the MR-BS. After receiving the MR_Generic-ACK message from the RS, the MR-BS shall also
respond with the MR_Generic-ACK message to the RS. After receiving the MR_Generic-ACK message from
the MR-BS, the MR-BS and the RS shall complete the RS network entry and enter operational state.
In the operational state, the non-transparent RS shall start transmitting its own frame start preamble at a
specified frame, whereas a transparent RS shall continue to monitor the frame start preamble transmitted by the
superordinate station. A RS may transmit the R-amble as per the instruction received in the RCD message. (see
section 8.4.6.1.1.4).
If RS frame offset TLV is included in RS_Config-CMD, the RS shall start its frame with the frame number as
indicated by RS_frame_offset TLV in RS_Config-CMD. The RS shall keep the difference to the frame number
used by the superordinate station as indicated RS_frame_number TLV in RS_Config-CMD.
Wait for RS_Config-CMD
RS_Config-CMD
Stop TConfigCmd
No
Non-transparent mode?
Yes
Wait for R-amble synch.
R-amble synch.
MR_Generic-ACK (RS_Config-CMD)
Start TAckAck
Wait for MR_Generic-ACK (MR_Generic-ACK)
Figure vvv—Handling RS_Config-CMD first reception at a RS
Wait for MR_Generic-ACK (MR_Generic-ACK)
RS_Config-CMD
Stop TAckAck
No
Non-transparent mode?
Yes
Wait for R-amble synch.
R-amble synch.
MR_Generic-ACK (RS_Config-CMD)
Start TAckAck
Wait for MR_Generic-ACK (MR_Generic-ACK)
Figure www—Handling RS_Config-CMD retransmission at a RS
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Wait for MR_Generic-ACK (MR_Generic-ACK)
MR_Generic-ACK (MR_Generic-ACK)
Stop TAckAck
RS is operational
Figure xxx—Handling RS operational confirmation at a RS
Perform operation parameter configuration
RS_Config-CMD
Start TConfigAck
Wait for MR_Generic-ACK (RS_Config-CMD)
MR_Generic-ACK (RS_Config-CMD)
Stop TConfigAck
MR_Generic-ACK (MR_Generic-ACK)
RS is operational
Figure yyy—Configure operation parameters to a RS at a MR-BS
Wait for R-amble synch.
R-amble synch.
Start Lost R-amble
Stop Lost DL-MAP
Stop Lost UL-MAP interval
Stop T1
Stop T12
R-MAP synch. established
Synchronized
R-amble synch.
Timeout Lost R-amble
Reset Lost R-amble
Synchronize to Preamble
Synchronized
Preamble synch.
Start Lost DL-MAP
Synchronize to DL-MAP
DL-MAP
Figure zzz—R-amble synchronization at a nontransparent RS
10